New credit card technology threatens to put more "vulnerable" people in debt, financial experts fear.

Gone are the days of having to sign or enter a pin, new credit cards now allow customers to "wave" their card for purchases under $80.

University of Canterbury associate professor in marketing Ekant Veer said the contactless technology made it easier for people to spend money "without even thinking about it" as the transaction required "such low involvement" on their part.

He was concerned contactless credit cards could hurt those "most vulnerable".

"We are not talking about people who are good with money, but those not good with money - the most vulnerable in society - who are more likely to end up in debt," Veer said.

His wife, Unicia Veer, who has worked with people on the brink of bankruptcy, also had concerns about the new credit cards.

The budget education coordinator and tutor at Kingdom Resources said some already struggled to manage their money and the new technology, which further distanced people from transactions, would make it even harder.

"If it's easier to spend it's going to be harder to track . . . We're trying to get people to keep track of their spending."

She encouraged those struggling to manage their money to carry cash so they could physically see how much they were spending.

ANZ customer Jim Harre, who recently received one of the new Visa payWave cards when his expired, felt the contactless technology took the "awareness" out of spending.

"You're not having to stop and think that's X amount of dollars, you're not having to put a pin in."

The Hurunui District Council councillor was further frustrated he could not opt-out of the technology on his credit card.

However, an ANZ spokesman said customers could choose whether they wanted to use the option. Those who did not want to use the technology for purchases under $80 could treat it as a regular card and enter their pin or sign.